1. Defensive Driving/Accident Avoidance
I don't think there is much of anything here unique to Healeys, drive it
like you would a motorcycle, assume anything else on the road can kill you
and does not see you.
Inspect Brake system for leaks, inspect lines, if original you might
consider replacing them.
Inspect tires for cracks and wear, lots of times our tires expire due to age
rather than mileage. A tube tire generally goes flat much faster than a
tubeless. Loose spokes can cause tubes to pop.
Check wire wheel splines for excessive wear.
Check suspension, shock mounts etc, for worn bushes, broken mounts, loose
nuts and bolts.
Would suggest doing this each spring before driving season starts or before
Grease and lube suspension and chassis to keep things from wearing out, you
can do the inspection above at the same time.
3. Safety Mods:
3 point seat belts if not equipped, roll bar or full cage would probably be
helpful in the case of a bad crack up, but few will go that far, Halogen or
some brighter head lamps to better see and be seen.
Marginal Items, but if you subscribe to the every little bit helps school:
air horns, third brake light (the cynic in me sees this as marginal because
the person that will probably hit you wouldn't notice you brake lights